1. Field of the Invention
The present invention relates to an automatic ground coffee dispenser designed to be mounted on an automatic coffee maker.
2. Description of Related Art
Such an automatic ground coffee dispenser is disclosed in French patent # 2713906 and comprises a storage vessel containing ground coffee and means for transferring a serving of ground coffee to the brewing chamber of an automatic coffee maker via an outflow opening located in the bottom portion of the storage vessel. The means for transferring the ground coffee consist of a plurality of rotary serving paddles located in the bottom of the storage vessel and borne by a cylindrical element driven in rotation about the axis of the storage vessel by a motor group. Four other upper radial paddles are borne by a coupling element with a conical outer shape, are arranged immediately above the serving paddles in order to convey the ground coffee to the bottom of the storage vessel, and are driven in rotation by the same means as the first paddles. Because the storage vessel is removably installed in the machine, provision is made of coupling means between the motor group and the cylindrical paddle drive element. Although operation is satisfactory, it was noted that certain types of ground coffee had a natural tendency to agglomerate and form bridges or lumps inside the storage vessel, which are sometimes carried along in rotation by the paddles and as a result the ground coffee is no longer able to descend to the serving paddles. If the brewing chamber is no longer correctly supplied [with ground coffee], this poses significant operational problems, particularly in the scope of an automatic coffee maker.
A solution was described in German patent # 19714303, wherein the ground coffee serving device comprises two sets of rotary paddles and means for driving them in opposite directions. Hence a truncated conical bottom section bears a first set of paddles and upwardly extends to form a conical tip bearing a second set of paddles. The serving device has first means for driving the bottom section in rotation and, between the latter and the mixer, second means for reversing the direction of the first rotary movement and for transferring it to the tip part. According to the document, these means are pinions or pulleys. Although a better conveying of the ground coffee to the bottom of the storage vessel is achieved, the complicated construction of this device poses a major disadvantage by making the arrangement of the transmission mechanisms in a space limited by the dimensions of the conical piece difficult. Furthermore, the mechanism may jam if ground coffee particles penetrate the gap separating the two mobile parts, namely the mixer and the lower section.